In their most basic operation, devices for producing, transmitting, routing, receiving, storing, encoding, decoding, translating or displaying video signals generate output based on input provided to them. In a test mode, while screen parameters are being tuned or problems diagnosed, video devices, including video displays, such as computer or television monitors, or other types of screens are typically provided with an external test signal, which oftentimes is a pre-determined test pattern. There are many standard test patterns, including various lines and colors so that the display performance may be measured or tuned. There are also many standards for display formats, typically based on parameters for size, resolution, frame rate, color space, etc. Many displays are capable of producing output in multiple different formats.
Present systems for generating test patterns generally take one of three forms. In some systems, particular circuits such as ASICs (Application Specific Integrated Circuits) or FPGAs (Field Programmable Gate Arrays) loaded with proprietary designs are used to generate the test patterns directly from such hardware. In these systems each test pattern is “hard-coded” for each format and cannot be modified once implemented. Other systems use a memory to store a series of binary equations that, when executed by a processor, generate the test patterns. The binary equations are generally stored in memory and are difficult to modify because they use proprietary tools to create and edit the equation files. Additionally, it can be difficult to understand the end result of modifying any of the equations. More commonly, test patterns are directly stored in memories in bitmapped files, with separate memories, or separate portions of a large memory used for each test pattern bitmap. Each display format also requires its own set of test patterns, and the size of the test pattern bitmap increases with each new generation of higher resolution displays.
It is becoming increasingly expensive to produce test pattern generating systems because of the increased resources necessary to produce all of the required patterns in the multitude of formats used in the industry today. Additionally, as described above, it is difficult to modify the test pattern content in prior art systems.
Embodiments of the invention address these and other problems in the prior art.